The invention generally relates to a motion damper. More specifically, this invention relates to a motion damper for use with vehicle accessories.
Damping devices are used on a variety of vehicle accessories such as console storage bins, glove boxes, slide-out trays and container holders, grab handles, door handles and coat hooks. For example, with console storage bins, which are often integrated into an overhead console, damping devices are typically incorporated into the pivot for a mounted door to provide a smooth, controlled opening action. Similarly, for spring-loaded slides such as those used in container holders or the like, a damping device is often used to control the slide motion as it is extended and retracted. Also, for grab handles, door handles and coat hooks, a damping device is often incorporated into the pivot for the handle or hook, whereby the pivoting motion is controlled and smooth as the handle or hook is extended and retracted.
A conventional damping device is a housing filled with a viscous damping fluid such as silicone, in which a paddle wheel on an axle is mounted with the axle extending from the housing and terminating in an external gear. The housing is typically secured to a structure mounting the movable feature, while a gear on the movable feature engages the gear on the axle of the viscous damping device to slow the movement of the movable feature. Although these damping devices provide the desired control, the devices typically require specific structure that adds to the expense of the vehicle accessory in a highly cost competitive environment.
Another difficulty with viscous damping devices for vehicle accessories is that performance changes with the wide range of temperature fluctuations encountered in the vehicle environment. For a viscous fluid, as the temperature decreases, viscosity increases dramatically. Correspondingly, as the temperature increases, the viscosity decreases. The result is an inconsistent feel to the vehicle accessory. Thus, viscous dampers used in present vehicle accessories provide a compromised performance at a premium price.
A friction damper for a vehicle accessory according to the invention includes an O-ring on a pivot axle of a rotatable member. The O-ring and pivot axle are received in abearing of a stationary mount. The O-ring is disposed between the pivot axle and the bearing for damping rotation of the rotatable member relative to the stationary member. In a variation of this embodiment, the pivot axle includes a circumferential arcuate channel for seating the O-ring. Alternatively, two or more O-rings can be used for damping rotation of the rotatable member relative to the stationary member. Further, the amount of damping can be varied by changing the fit between the pivot axle, O-ring and bearing. Also, different materials for the O-ring and bearing alter the amount of damping action.
In a further variation of the invention, the bearing is slidably received in the stationary mount, and includes a tab for reception in a slot in the stationary mount, whereby the bearing is blocked against rotation relative to the stationary mount. Further, the pivot axle may also be slidably received in the rotatable member for rotation therewith.
Also according to the invention, a vehicle accessory includes a rotatable member having a pivot axle, a stationary mount including a bearing for receiving the pivot axle, and a damper including an O-ring disposed between the pivot axle and the bearing for damping rotation of the rotatable member relative to the stationary mount. The rotatable member may, for example, be a grab handle in a vehicle interior. Preferably, the pivot axle includes a circumferential arcuate channel, and the O-ring is seated in the channel. Alternatively, two or more O-rings are disposed between the pivot axle and the bearing for damping rotation of the rotatable member relative to the stationary member.
In a variation of this embodiment, the bearing is slidably received in the stationary mount. Preferably, the bearing includes a tab for reception in a slot of the stationary mount, whereby the bearing is blocked against rotation relative to the stationary mount. Similarly, the pivot axle may also be slidably received in the rotatable member for rotation therewith.